Study on photocatalytic performance of carbonated coating supported TiO2@SiO2

In recent years, photocatalytic cement-based materials have demonstrated a positive impact on reducing air pollutants. However, challenges arise from the aggregation of photocatalysts and the intricate internal environment of cement-based materials, resulting in diminished photocatalytic efficiency. To address these issues, the TiO2@SiO2 photocatalyst which reduced agglomeration and was easy to disperse was prepared by sol-gel method, and the TiO2@SiO2 photocatalyst was added into γ-C2S carbonated cementitious material system by surface loading and blending to prepare the photocatalytic carbonation coating. In this paper, the TiO2@SiO2 photocatalyst synthesized at solution pH 4.16 had the highest photocatalytic degradation efficiency of nitrogen oxides. The photocatalytic efficiency of the prepared carbonated coating was evaluated through the degradation efficiency of nitrogen oxide and rhodamine B. When the content of TiO2@SiO2 was 7%, the photocatalytic carbonation coating had the highest photon removal efficiency for NO (0.17%), and the degradation rate for rhodamine B was 32.94% after 7 h illumination. The photocatalytic effect of the photocatalytic carbonated coating prepared with surface loaded TiO2@SiO2 was better than that of the doped coating. When the surface loading was 1.5 g/m2, the photocatalytic efficiency of the coating on NO reached 0.81%, and the degradation rate of rhodamine B after 7 h illumination was 36.92%. This method introduced a novel concept for the future application of photocatalytic building materials, contributing to carbon sequestration and energy conservation efforts.